New limits on the axion-nucleon coupling over the axion mass region 10−24≤ma≤5×10−21 eV are derived by reanalyzing data from laboratory measurements on Lorentz and CPT violations. These results establish the first laboratory constraints on the axion-nucleon coupling for axion masses below 10−22 eV. For 10−22≤ma≤5×10−21 eV, the results improve upon previous laboratory limits by more than three orders of magnitude, exceeding for the first time the astrophysical limits from supernova SN1987A cooling. For the axion mass range of interest corresponding to ultralow frequencies, the crucial local phase of the axion field is considered. Furthermore, the obtained limits are nearly equivalent to those projected for a recently proposed experiment employing high-intensity neutron beams at the European Spallation Source. For an alternative type of axion-nucleon interaction, the quadratic wind coupling, the constraints exceed the current best results by approximately two orders of magnitude.
Zhang et al. (2025) studied this question.